Phase II tensile properties of self-assembled cartilage constructs. (A) Tensile stiffness for all groups. Treatment with 4α-PDD, ouabain, and their combination resulted in significant increases in Young’s moduli compared to control (91%, 103%, and 107% increases, respectively), but no differences between each other. (B) Tensile strength for all groups. Treatment with ouabain or with the combination of 4α-PDD and ouabain improved construct UTS (141% and 136% increases over control, respectively), followed by treatment with 4α-PDD (91% increase over control, but not statistically significant). Data are presented as means + standard deviations. Lowercase letters denote significant differences; groups not connected by the same letter are considered significantly different (p<0.05).